Heretofore, polyolefins such as polyethylene and polypropylene when utilized as a plastic component in thermoplastic elastomers had an upper end use temperature of less than 150.degree. C. Accordingly, these compositions had limited end use applications as in under the hood applications of a vehicle where high temperatures are encountered and where low oil swell is desirable.
U.S. Pat. No. 4,409,365, to Coran and Patel relate to thermoplastic rubber blends which have good oil resistance and comprise monoolefin rubber and nitrile rubber.
U.S. Pat. No. 5,073,597, to Puydak, Hazelton and Ouhadi relate to dynamically vulcanized compositions having good tensile strength and include a first butyl or halobutyl rubber-based elastomer and a second EPM and/or EPDM elastomer in a matrix of a crystalline polyolefin resin.